Safety control for machines having opening and closing movements



Dec. 21, 1943. B, YANCHENKO 2,337,143

SAFETY CONTROL FOR MACHINES HAVING OPEI IING AND CLSING MOVEMENTSFiledMay 11, 1942 4 Sheets-Sheet l INVENTOR BASIL J. YANCHENKO ATTORNEYSDC. 21, 1943. YANCHENKO 2,337,143

SAFETY CONTROL FOR MACHINES HAVING OPENING AND CLOSING MOVEMENTS FiledMay 11, 1942 4 Sheets-Shee t 2 i 35 N FIG. 2 I 32 28 33 31 I8 29 38 f)20 2s girl/ll 'INVENTOR BASIL J. YANQHENKO ame d/W 'TORNEYS Dec. 21,1943. YANCHENKO 2,337,143

SAFETY CONTROL FOR NACHINES HAVING OPENING AND CLOSING MOVEMENTS FiledMay ll, 1942 4- SheefiS-S'neet 3 i 2 l m, may a I I ZMVENTOR EAS H. J.YAf-ECHEMKO ATTO R N LYS B. J. YANCHENKO 2,337,143

SAFETY CONTROL FOR MACHINES HAVING OPENING AND CLOSING MOVEMENTS FiledMay 11', 1942 4 Sheets-Sheet 4 F595 7 FIG. 4

5' 2; a I M N i I J a v INVENTOR BASIL J. YANCHENKC BY J @aM n/MATTORNEYS Patented Dec. 21, 1943 SAFETY CONTROL FOR MACHINES HAVINGOPENING AND CLOSING MOVEMENTS Basil J. Yanchenko, Syracuse, N. Y.,assignor to The Prosperity Company, Inc., Syracuse, N. Y., a corporationof New York Application May 11, 1942, Serial No. 442,480

10 Claims.

, This invention relates to safety controls for machines including ahead cooperating with a work support or anvil, as for instance ariveting machine, in which the riveting head or punch is actuated by apressure-operated, or cylinder and piston, motor, and has for its objecta safety control for a pedal operated machine, which includes a timingdevice for de-energizing the motor a predetermined time period, after ithas actuated the head or punch, or for temporarily taking the controlaway from the pedal, so that pressure Will be relieved, regardless ofwhether the pedal is held depressed, and also by which repeatedoperations, upon one operation of the pedal, are prevented.

The invention further has for its object a safety control embodying thetiming device and wherein a power operated guard controlled by the footpedal moves in advance to the head or punch, and if the guard encountersno obstruction, the power is relayed or transferred to a device foropening a master control or master valve, permitting the motor of themachine to be energized, but if the guard encounters an obstruction, thepower is prevented from being relayed to operating means for the mastercontrol or valve.

The invention further has for its object a safety control for smallriveters, as so-called squeeze riveters, which is particularly simple,sure, accurate in operation, and highly eflicient in use.

The invention consists in the novel features and in the combinations andconstructions hereinafter set forth and claimed.

In describing this invention, reference is had to the accompanyingdrawings in which like characters designate corresponding parts in allthe views.

Figure 1 is a fragmentary side elevation, partly in section, of asqueezeriveter equipped with this invention or showing this inventionapphed to a squeeze riveter.

Figure 2 is an enlarged sectional view of parts seen in Figure 1, themachine being shown in its open position.

Figure 3 is a view similar to Figure 2 showing the machine in operatedposition, or while operated.

Figure 4 is a fragmentary view of parts seen in Figure 2 showing theaction of the guard and the control mechanism, when the guard encountersan obstruction, as the thumb of the operator.

Figure 5 is a fragmentary detail view of the timing device for timingthe closing of the master valve or taking the control away from thepedal.

Figure 6 is an enlarged sectional view on line 66, Figure 4.

Figure 7 is a fragmentary detail view, showing a slightly modified formof guard used when a channel or cup shaped part is to be riveted t abase strip.

The construction of the squeeze riveter itself forms no part of thisinvention, and in so far as this invention is concerned, it may be ofany suitable form, size and construction.

I designates the upper portion of the frame of the squeeze riveter,which carries the work support and the movable head or punch, this beingsupported on a suitable pedestal 2 rising from a base 3. 4 designatesthe work support or anvil, and 5 a movable head or punch suitably guidedin a passage'formed in the head 6 of the motor for actuating the head orpunch 5. In machines of this character, the head Or punch 5 is usuallyoperated by a pneumatically operated motor, and hence, as here shown,the motor includes a cylinder I and a piston 8 movable therein. Themotion of the piston is transferred to the head or punch 5 throughsuitable motion transmitting mechanism, not shown, including a part 9coacting with the upper end of the head or punch 5. The punch 5 isactuated by the piston 8 against the action of a suitable returningspring Ill. The piston 8 is returned to its starting position, usuallyby ,a second piston I workin in a suitable cylinder I2 andhaving its rodI3 connected to the piston 8. The control of the air to and from thecylinder I is effected by a master control valve tobe hereinafterdescribed.

The cylinder I2 is in open communication with the feed line at alltimes, but the piston II is of.

much smaller pressure area than the piston 8,.

so that when the master valve is opened, the piston 8 overcomes thepiston II, and when the master valve is closed and the air is free toexhaust from the cylinder I, the piston II returns the piston 8 tostarting position, and thereby permits the head or punch 5 to return toopen position. The construction thus far described per se forms no partof this invention.

This invention relates to the control of the flow of power, and in thisinstance, a pressure fluid, to the motor for the head 5, means forautomatically timing the de-energization of the motor a predeterminedtime, regardless of any operator J control, as a foot pedal, even thoughthe foot pedal is held depressed, and also a power-operated guard, andmeans for relaying the power to means for operating the master valve,after the guard has been moved to safety position.

As the motive fluid is compressed air, and the motor a pneumatic motor,the master control is a valve. [4 designates the master control valve,this being shown as mounted upon or assembled with the cylinder 1. andhaving a movable member including a normally closed intake valve head I5and a normally open exhaust valve head [6, these being connectedtogether, so that they act as a unit, the intake end of the casingcommunicating with a suitable main feed or service line or pipe I? andthe exhaust end of the casing communicating with the outer air through apassage I8. The valve communicates through a passage IS leading from thevalve casing from between the valve heads into the upper end of thecylinder 1. The movable valve member consisting of heads [5, it areoperated against a re turning spring 29. The master valve M iscontrolled in its movement to open the intake head [5 and close theexhaust head 16 by a pedal 2 through suitable mechanism.

In the illustrated embodiment of the invention, the pedal operates. acontrol valve 22 which controls the flow of air to a pressure-operateddevice 23, the movable member of which is a plunger 24 acting through amotion transmitting memher, as a slide 25, on the unit or one movablemember of. the master valve. The pressure-operated device is here shownas a diaphragm chamber having a diaphragm 26 therein thrusting againstahead on. the plunger 24. The slide 25, against which the plunger 24acts, is slidable in the valve casing l4 against the action of areturning spring 2], and embodies a thrust member normallythrusting-against the stem 28* on the movable member of: the mastervalve and being shiftable by a timer device out of its normal position,to permit the intake head 15 and the master valve to close and theexhaust valve head it to open a predetermined. time after the mastervalve has been: opened, eventhough the pedal 2 l is held depressed andthe diaphragm chamber held under pressure.

This timer means consists of a cylinder 28 mounted on, or assembled as,a unit with, the master unit l4, and having a. piston 29 therein,thrusting against the thrust member 30 previously referred to, carriedby and. movable relatively to the motion transmitting member or slide25, it-being normally in position to transmit motionto operate themaster valve and shiftable into position to permit the master valve toshift to normal, position, wherein. the intake is closed and the exhaustopen. The thrust. member is here. shown as shiftable diametricallythrough the slide. 2.5. and normally thrusting against the stem, 28 ofthe movable member of the master valve. The thrust member 30 has a notch3| therein arranged to be brought into alinement with the stem 23* topermit the intake valve head IE to close and the exhaust valve head toopen. The shifting of the thrust member 30 is effected by the piston 29in the timer cylinder 28. The timer cylinder 28' is connected on thepressure side of the piston 29 to the casing of the valve 14 through arestricted port or conduit 32 of such size as to require a definite timeperiod to build up pressure in the cylinder 28 sufiiciently to actuatethe piston 29 to shift the thrust member 30 against the action of areturning spring 33. The spring 33 acts on the piston 29. Also, areturning spring 34 acts on the member 39. The spring 33 is shown asinterposed between an annular shoulder at the inner end of an adjustingscrew 35 threading into the head of the cylinder 28, and against aninternal annular shoulder 36 on the piston 29. The piston 29 is hereshown as cup-shaped and the screw extends into the cup-shaped piston.The returning spring 34 for the latch 30 is located in the bottom of thetransverse passage in which the thrust member 30 slides, and the springis interposed between the lower end of the thrust member 33 and thebottom of the passage.

When the master valve is operated by the diaphragm chamber 26 in thechamber 23, this occurring upon the operation of the foot pedal 21, theintake Valve head I5 is opened and the eX- haust valve head It closed,and the parts assume the position shown in Figure 3, permitting air toflow from the feed line I! through the master valve and the passage l9thereof into the upper end of the cylinder l, actuating the pistontherein, and moving the head or punch 5 downward into the position shownin Figure 3. During this operation, the slide 25 is actuated by theplunger 24 from the position shown in Figure '2 to that shown in Figure3, carrying the thrust member 30' therewith. The notch 3| is out ofalinement with the stem 28 of the movable member of the master valveduring this operation. When the master valve is thus operated, pressurebuilds up over a predetermined time period in the timer cylinder 28through the restricted or small pipe 32, overcomes the resistance of thespring 33, acting on the timer piston 29 and the spring 34 acting on thethrust member 33. When the pressure builds up sufficiently to overcomethese springs, the thrust member is shifted from the position shown inFigures 2 and 3 to that shown in Figure 5, bringing the notch 3| intoregisterwith the steam 28 of the movable member of the master valve.This permits the spring 20 to close the intake valve head I5- and openthe exhaust valve head [6 of the master valve, so that air exhausts fromthe cylinder 1 and the piston 8 is drawn upwardly by the air pressure inthe cylinder l2 against the lower side of the piston II. The cylinder I2is in open communication with the main feed line through pipes 37 and38. The timing is such that the head or punch 5 is moved into engagementwith the end of the rivet, and then a squeezing pressure applied andheld long enough to permit the rivet to set.

The control of the flow of air to the pressureoperated means ordiaphragm chamber 23 and the operation of the guard will now bedescribed. 46 designates a. guard in the form of a ringaround the pathof the head or punch 5, this guard being power-operated, controlled bythe pedal 2|, and movable in advance of the head 5 from the positionshown in Figures 1 and 2, to that shown in Figure 3, and the movement ofthe guard into position shown in Figure 3 controls the flow of motivefluid to the pressure-operated means or diaphragm chamber 23 for themaster valve M. The guard 45! is here illustrated as actuated by a.piston i l movable in a cylinder 45, which, for the sake of convenience,may be called a relay cylinder. The piston 44 has a rod 46 to which iscoupled a stem d1 carr ing an arm or bracket 48 rigid with the guardring Ml. The piston 44 is double acting or has upper and lower pressurefaces d9, 50, the upper pressing face "39 being of greater pressure areathan the lower pressing face 5i), due to the fact that the piston rod itreduces the pressure area of the pressure face 50. The upper end of thecylinder 45 is connected in the feed line through a conduit in which isconnected the pedal operated control valve 22, this being located withinthe pedestal 2, the pedal 2| being also pivoted to the pedestal 2. Thevalve 22 is of the self-returnable combined intake and exhaust type andembodies a normally closed intake valve head 52 and a normally openexhaust valve head 53, these being connected together, so that they actas a unit, the unit being acted upon by a returning spring 54. The pedal2|, through an arm 55, transfers its movement to the valve unit througha plunger 53. The operating movement of the pedal is against a returningspring 58. The intake end of the valve casing of the valve 22 isconnected in a main air supply through a pipe 59. When the pedal 2| isdepressed, the intake valve head 52 is opened and the exhaust valve head53 closed, permitting air to pass from the main line 59 through thevalve casing, conduit 5| to the upper end of the relay cylinder 45 andactuate the piston 44 against the opposing air pressures from the mainline through pipe 33, thus lowering the guard 40 into the position shownin Figure 3, unless the guard should be obstructed, as shown in Figure4.

Assuming that the guard is not obstructed, then the piston 43 can travelits full movement, and at the end thereof, uncovers a port 66] in therelay cylinder 45, which is connected by a conduit iii to the pressureside of the diaphragm chamber 23. If, however, the guard is obstructed,as shown in Figure 4, the piston 44 does not travel far enough touncover the port 60, and hence the pressure-operated means or diaphragmchamber 23 is not energized, and the master valve remains closed. andhence the punch 5 does not operate.

In order to prevent building up of pressure in the cylinder 45 on thepressure face 49 of the piston sufficiently to actuate the piston 44 touncover the port 60, when the guard 40 is obstructed in its movement, anexhaust port 64 is provided in the side of the cylinder 45 and locatedbetween the pressure faces of the piston at all times to permit theexhaust of any air that might pass the end of the piston provided withthe pressure face 49, This exhaust port 64 also permits the exhaust ofany air passing the lower pressure face 53 of the p ston 44. To effectthe passage of air that might work past the piston heads or faces, thepiston 44 is formed with a lengthwise groove 62 into which the port 53opens and with a circumferential groove 63.

The stem t! for supporting the guard 43 is adjustably mounted in the rod46 of the piston, and as here shown, the piston is formed with an axialpassage extending inwardly from its lower end for receiving the stem 41.The end of the piston rod is split or formed with four lengthwise slotsand is also threaded for receiving a nut 65. The nut and the threadedend of the piston rod 4| form a compression coupling. The stem 4'! isnon-circular or square and the stem 26 formed with four slots. Thecorners of the square are seated in the slots, and when the nut 65 istightened, the square stem 4'! is tightly clamped against rotation andaxial displacement. The piston 44 is also held from rotation in itscylinder 45 by a screw or key 63 extending through the cylinder wallinto a lengthwise slot 61 in the piston. ihe stem 43 of the ring-shapedguard 40 is also adjustable lengthwise to accurately locate the guard orguard ring 40, and as here shown, the stem 48 extends through a collar68 in the lower end of the stem 4! and is held in its adjusted positionby a clamping screw 69. The cylinder may also be mounted for ver-, ticaladjustment on the main cylinder 1, it being shown as carried by a baseplate 10 having a vertical slot or slots H therein for receiving screws12 threading into the cylinder I.

In Figure '7, the guard is shown as in the form of a sleeve 40 and asconnected by an angular arm to the piston rod 46 This sleeve type ofguard 40 is used when a channel or cup shaped part as C is to be rivetedto a base strip D through the bottom of the cup or channel shaped part Cand is of such diameter as to enter the channel through the open sidethereof. If the operator should take hold of the work with the thumb ora finger on the edge of the part C, the guard 40* will be obstructed inits downward movement and held from movement into the channel, and hencethe punch 5 will not be actuated.

The general operation is as follows:

The operator places two strips of work to be riveted together with arivet through alined holes therein on the anvil 4 holding his fingersout of the path of the guard 40. He then depresses the pedal 2|,operating the pedal controlled valve 22 to permit the flow of air to theupper end of the cylinder 45, actuating the piston 44 therein, to movethe guard from the position shown in Figures l and 2 into the positionshown in Figure 3, this movement uncovering the port 6!] in the cylinder45, permitting air under pressure to flow through the pipe 6| to thepressure side of the diaphragm chamber 23, actuating the diaphragm 26therein and the plunger 24, to operate the movable member of the mastervalve from the position shown in Figure 2 to that shown in Figure 3,thus permitting air to enter the cylinder 1 of the main motor andactuate the punch or head 5. During this operation, the air pressure inthe timer cylinder 28 is being built up and when it is built up to apredetermined extent, the piston 29 of the timer cylinder actuates thelatch from the position shown in Figure 2 to that shown in Figure 5,permitting the movable member of the master valve to return to itsnormal position (Figure 2), and hence permitting the air to exhaust fromthe cylinder 1 and the punch or head 5 to open. The piston 8 in thecylinder 1 is moved upwardly or returned to its starting position by thepressure in the cylinder I 2 against the piston ll. Phe operation of thetimer cylinder and pistons 28 and 29 takes the control away from thepedal 2| and the control valve 22, so

that the pedal must be released before another operation can take place.

If, however, the operator so holds the work that the guard encounters afinger or portion of his hand, as seen in Figure 4, the piston 44 in therelay cylinder 45 can not travel far enough to uncover the port 69, andhence the diaphragm chamber 23 will not be energized and the mastervalve will not be operated.

A guard operated by a cylinder and piston,- which also operates to relaythe flow of power to some other device to be operated, per se, forms nopart of this invention, but constitutes the subject matter of my pendingapplication, Serial Number 433,366, filed March 4, 1942.

What I claim is:

l. A safety control for machines which include a head movable toward andfrom a cooperating work support, and a motor for actuating and applyingpressure to the head, the safety control.

including a power line, a master control element therein for controllingthe flow of power to the motor and normally arranged to cut off the flowof power to the motor, a pedal controlled means for operating the mastercontrol element, and a timing device controlled by the master controlelement and operable to effect the return of the master control elementto its normal position independently of the pedal controlled means,after the pedal has been held operated a predetermined time.

2. A safety control for machines which include a head movable toward andfrom a cooperating work support and a pressure-operated motor foractuating and applying pressure to the head, the safety controlincluding a conduit line for a pressure fluid, a combined intake andexhaust self-returning master valve therein normally arranged with itsintake closed and its exhaust open, a pedal controlled means foroperating the master valve to open its intake and close its exhaust, anda pressure-operated timing device controlled by the master valve foreffecting the return of the master valve to its normal positionindependently of the pedal operated means after the pedal has been heldoperated a predetermined time.

3. A safety control for machines which include a head movable toward andfrom a cooperating work support, and a pressure-operated motor foractuating and applying pressure to the head, the safety controlincluding a conduit line for a pressure fluid, a combined intake andexhaust selfret'urning master valve therein normally arranged with theintake closed and the exhaust open, a pedal controlled means foroperating the master valve to open its intake and close its exhaust, anda timing device controlled by the master valve for effecting the returnof the master valve to its normal position independently of the pedaloperated means, after the pedal has been held operated a predeterminedtime.

4. A safety control for machines which include a head movable toward andfrom a cooperating work support and a pressure-operated motor foractuating and applying pressure to the head, a safety control includinga feed line for a pressure fluid, a combined intake and exhaustselfreturning master valve therein normally arranged with its intakeclosed and exhaust open, pressure-operated means, and a feed linetherefor operating, when energized, to open the intake and close theexhaust of the master valve, a pedal operated self-returning intake andexhaust control valve in the feed line, a cylinder connected in the feedline controlled by the pedal operated valve, a piston therein, a guardoperated by the piston in advance of the head, and a conduit connectingthe cylinder and the pressure-operated motor through a port located tobe passed by the piston, when the piston has traveled a predetermineddistance.

5. A safety control for machines which include a head movable toward andfrom a cooperating work support and a pressure-operated motor foractuating and applying pressure to the head, a safety control includinga feed line for a pressure fluid, a combined intake and exhaustselfreturning master valve therein normally arranged with its intakeclosed and exhaust open, pressure-operated means, and a feed linetherefor operating, when energized, to open the intake and close theexhaust of the master valve, a pedal operated self-returning combinedintake and exhaust control valve in the feed line, a cylinder connectedin the feed line controlled by the pedal operated valve, a pistontherein, a guard operated by the piston in advance of the head, aconduit connecting the cylinder and the pressure-operated device througha port located to be passed by the piston when the piston has traveled apredetermined distance and hence moved the guard a predetermineddistance, and a pressure-operated timer device controlled by the mastervalve and operable to effect the return of the master valve to itsnormal position independently of the pedal operated valve and thepressure-operated means for master valve, after the pedal has been heldoperated a predetermined time.

6. A safety control for machines which include a head movable toward andfrom a cooperating work support and a pressure-operated motor foractuating and applying pressure to the head, a safety control includinga feed line for a pressure fluid, a combined intake and exhaustselfreturning master valve therein normally arranged with its intakeclosed and exhaust open pressure-operated means, and a feed linetherefor operating, when energized, to open the intake and close theexhaust of the master valve, a pedal operated self-returning combinedintake and exhaust control valve in the feed line, a cylinder and apiston therein, a guard operated by the piston in advance of the head,conduits for pressure fluid connecting the cylinder in the feed line atopposite ends of the cylinder, the pressure faces of the pistons beingof different pressure areas and the conduit connected to the end of thecylinder in which the piston face of less area is presented being inopen communication with the feed line, the other end of the cylinderbeing connected in the feed line controlled by the pedal operated valve,and a conduit connecting the cylinder and the pressure-operated devicethrough a port located to be uncovered by the piston, when the pistonhas traveled a predetermined distance from starting position.

7. A safety control for machines which include a head movable toward andfrom a cooperating Work support, and a pressure-operated motor foractuating and applying pressure to the head, a safety control includinga feed line for a pressure fluid, a combined intake and exhaustselfreturning master valve therein normally arranged with its intakeclosed and exhaust open, pressure-operated means, and a feed linetherefor operating, when energized, to open the intake and close theexhaust of the master valve, a pedal operated self-returning combinedintake and exhaust control valve in the feed line, a cylinder and apiston therein, a guard operated by the piston in advance of the head,conduits for pressure fluid connecting the cylinder in the feed line atopposite ends of the cylinder, the pressure faces of the pistons beingof different pressure areas and the conduit connected to the end of thecylinder in which the piston face of less area is presented being inopen communication with the feed line, the other end of the cylinderbeing connected in the feed line controlled by the pedal operated valve,and a conduit connecting the cylinder and the pressureoperated devicethrough a port located to be uncovered by the piston, when the pistonhas traveled a predetermined distance from starting position, saidcylinder having an exhaust port located to exhaust to the outer air anypressure fluid passing the pressure faces of the piston.

8. A safety control for machines which inelude a head movable toward andfrom a cooperating work support, and a motor for actuating and applyingpressure to the head, the safety control including a power line, amaster control element therein for controlling the flow of power to themotor and normally arranged to cut oil. the flow of power to the motor,pedal controlled means for operating the master control elementincluding a movable motion transmitting part, a shiftable thrust membercarried thereby and normally arranged to transmit motion to the mastercontrol element and shiftable relatively to the motion transmitting partto permit the master control element to return to starting position.independently of the pedal operated control means, and a timing devicecontrolled by the master control element and operable to shift thethrust member out of thrusting position to effect the return of themaster control element to its normal position independently of the pedalcontrolled means after the pedal has been operated a predetermined time.

9. A safety control for machines which include a head movable toward andfrom a cooperating Work support and a pressure-operated motor foractuating and applying pressure to the head, the safety controlincluding a conduit line for a pressure fluid, a combined intake andexhaust selfreturning master valve therein, normally arranged with itsintake closed and its exhaust open, pedal controlled means for operatingthe master valve to open its intake and close its exhaust including aslide, a thrust member carried by the slide and shiftable relativelythereto and normally arranged to transmit motion to the master valve tooperate it and shiftabl into a position to permit the master valve toreturn to its starting position, and a pressure-operated timing devicecontrolled by the master valve for shifting the thrust memberindependently of the slide into position to permit the return of themaster control valve to normal position.

10. A safety control for machines which include a head movable towardand from a cooperating work support and a motor for actuating andapplying pressure to the head, the safety control including a powerline, a master control element therein for controlling the flow of powerto the motor and normally arranged to cut oil the flow of power to themotor, a self-returnable pedal controlled means for operating the mastercontrol element from normal position, a second power operated motorconnected in the power line including a movable member, the mastercontrol element also controlling the flow of power to said second motor,a guard operated by the said movable member in advance of the head, andconnecting means between the second motor and the first for controllingthe flow of power to the first motor after said movable member and theguard actuated thereby has traveled a predetermined distance.

BASIL J. YANCI-IENKO.

